Specific Thin Layer Chromatography Research Articles

A Specific Thin Layer Chromatography Method for the Identification and Separation of Medium Chain Acylglycerols.

Medium chain fatty acids (MCFAs), have gained nutritional relevance in the past few years. They are continuously used in obtaining structured lipids like medium chain acylglycerols (MCAs) for various purposes. However, because of their chemical structure pertaining carbon chain length and the presence of saturated and unsaturated fatty acids, sensitive detection techniques are required for their correct identification and separation. In the present work, a specific thin layer chromatography (TLC) method for MCAs was developed. The proposed method consisted of the use of a mixture of hexane: acetone (70:30 v/v) as mobile phase, since it proved effectiveness for the separation of compounds of interest (MCAs) as well as having the necessary sensitivity to separate different species of monoacylglycerols (MAGs), diacylglycerols (DAGs) and triacylglycerols (TAGs) of MCFAs. For observation of the compounds, a single oxidizing agent was not sufficient, thus a combination of visualization reagents was used (first a 10 % solution of sulphuric acid in methanol followed by a 10 % solution of phosphomolybdic acid in methanol) achieving the correct visualization of the desired compounds.

Simultaneous HPTLC determination of strychnine and brucine in strychnos nux-vomica seed.

Objective:A simple, sensitive, and specific thin layer chromatography (TLC) densitometry method has been developed for the simultaneous quantification of strychnine and brucine in the seeds of Strychnos nux-vomica.Materials and Methods:The method involved simultaneous estimation of strychnine and brucine after resolving it by high performance TLC (HPTLC) on silica gel plate with chloroform–methanol–formic acid (8.5:1.5:0.4 v/v/v) as the mobile phase.Results:The method was validated as per the ICH guidelines for precision (interday, intraday, intersystem), robustness, accuracy, limit of detection, and limit of quantitation. The relationship between the concentration of standard solutions and the peak response was linear within the concentration range of 50–1000 ng/spot for strychnine and 100–1000 ng/spot for brucine. The method precision was found to be 0.58–2.47 (% relative standard deviation [RSD]) and 0.36–2.22 (% RSD) for strychnine and brucine, respectively. Accuracy of the method was checked by recovery studies conducted at three different concentration levels and the average percentage recovery was found to be 100.75% for strychnine and 100.52% for brucine, respectively.Conclusions:The HPTLC method for the simultaneous quantification of strychnine and brucine was found to be simple, precise, specific, sensitive, and accurate and can be used for routine analysis and quality control of raw material of S. nux-vomica and several unani and ayurvedic formulations containing this as an ingredient.

Development and Validation of a TLC-Densitometric Method for the Simultaneous Quantitation of Strychnine and Brucine from Strychnos spp. and its Formulations

A simple, sensitive, and specific thin-layer chromatography densitometric method has been developed for the simultaneous quantitation of strychnine and brucine. These two marker compounds are quantitated in the seeds of Strychnos nux-vomica, Strychnos ignatii, and its formulations. The method involves densitometric evaluation of strychnine and brucine after resolving it by high-performance TLC on silica gel plate with toluene-ethyl acetate-diethyl amine-methanol (7:2:1:0.3 v/v) as the mobile phase. The method is validated for precision (interday and intraday), repeatability, and accuracy. The relationship between the concentration of standard solutions and the peak response is linear within the concentration range of 160 to 480 ng/spot for strychnine and 80 to 480 ng/spot for brucine. Instrumental precision is found to be 0.54 and 0.78 (% CV), and repeatability of the method is 1.01 and 1.06 (% CV) for strychnine and brucine, respectively. Accuracy of the method is checked by recovery study conducted at three different levels and the average percentage recovery is found to be 99.13% for strychnine and 100.16% for brucine. The proposed HPTLC method for the simultaneous quantitation of strychnine and brucine is found to be simple, precise, specific, sensitive, and accurate, and it can be used for routine quality control of raw material of Strychnos spp. It also can be applied in quantitating any of these marker compounds in other formulations.

Extracellular microbial lipids from pseudomonas SpLS1as bioemulsifiers

Abstract Microbes have been isolated from contaminated soil and wastewater by enrichment culture experiments for bioemulsifier production and cell free broth was tested for bioemulsifier by measuring surface tension, emulsifying activity. One of the strains, Pseudomonas sp LS1, was studied in detail for the production of bioemulsifier from different carbon sources for optimization of substrate concentration, its application and characterization. Pseudomonas sp LS1 is capable of reducing surface tension of glucose containing broth from 55 to 30 mN/m. The bioemulsifier production was growth associated. Preliminary structure identification with specific thin layer chromatography agent (CH3CI3 : MeOH : H2o :j 69 : 24 : 2) extracts showed, one spot having rhamnolipid structure with Rf value of 0.54. The rhamnolipid production by Pseudomonas Sp LS1 may have potential for facilitating the bioremediation of contaminated sites with water insoluble aromatics.

Plasma fucose and sialic acid concentrations during oral glucose tolerance tests in normal and diabetic (mellitus) humans

1. 1. The plasma fucose and sialic acid concentrations were determined during oral glucose tolerance tests in normal humans and in hospitalized patients with normal and impaired glucose tolerance. 2. 2. Measurement of the plasma fucose concentration by means of a specific thin layer chromatography—isotope dilution method and the method of Dische and Shettles demonstrates that no rise in fucose levels occurs in human subjects with normal or impaired glucose tolerance during an oral glucose tolerance test. 3. 3. The plasma sialic acid concentration does not change in either normal or diabetic (mellitus) individuals during an oral glucose tolerance test. 4. 4. The apparent rise in plasma fucose concentration during oral glucose tolerance tests in patients with impaired glucose tolerance which was reported by Shaw, Kryston and Mills is not due to a rise in true plasma fucose concentration.